Insulating-support for high-tension conductors.



R. D. MERSHON.

INSULATING SUPPORT FOR HIGH TENSION GONDUGTOBS.

APPLIOATIOI FILED IAY 21. 1907.

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R. D. MERSHON.

INSULATING SUPPORT FOR HIGH TENSION GONDUGTOBS.

APPLICATION FILED MAY 21. 1907.

Patented Apr. 13, 1909.

3 SHEETS-SHEET 2.

9 v Xi R. D. MERSHON.

INSULATING SUPPORT FOR. HIGH TENSION GONDUGTORS.

APPLIOATIOHIILED HAY 21. 1907.

917,785. Patented Apr. 13, 1909.

3 SHEETS-SHEET 3.

- RALPH D. MERSHON, OF NEW YORK, N. Y.

IIIIN'S ULATIN G-SUPPOBil. FOR HIGH-TENSION CONDUCTORS.

To ullaclzom it may concern:

Be it known that. I, Ranrn l). hhznsnox, a citizen of the United States, residing in the borough of Manhattan, city, county, and State of New York,have invented a certain new and useful Imprm'ement in Insulating- Supports for High-Tension Conductors, of which the following is a specification.

- Specification'of Letters Patent. Application filed Iay'21, 1907. Serial No. 374,928.

My present invention has especial relation 5 to means-for supporting and insulating electric conductors 'of long span intended to convey electricity at very high potentials.

Where power is to be transmitted over long distances high potentials are obviously essential. In most cases where such high voltages are used it is preferable to make use of long spans supported on high structures, One reason for such conusually of steel.

l l l struetions is the economy resulting from long span construction. Fewer polnts off support andtherefore fewer insulators are necessary where long spans are used and a this is desirable, not only because of the economy involved, but because fewer points are provided at which troubles due to defective insulation can occur. Long span construction, on the other hand, involveshigh wind strains, great weight and greater forces generally than in the caseof shorter spans and there are thus rendered necessary a correspondingly increased strength of insu- E lators and their supports. Under the conditions above named, it is clear that the ini sulator at each point of suspenslon must be calculated to resist, not only thegreat tendency to creeping, flashing and puncture considerable transverse and shearing strains as well, due to the forces incident to long spans of conductor. Hitherto bulky and heavy porcelain insulators have been used,

come the flashing and creeping losses, and supported and reinforced by steel insulator pins which introduce danger of puncture by direct passage of a high tension discharge there comes a point at whichtheir increased cost becomes prohibitory. T-his increase of expense is largely due to thedltticulty experienced in properly burning porcelain masses of such great bulk without deformation and breakage. Besides this the enlarge- Patented April 13, 1909.

ment of the petticoats, while it lengthens the path over which a'flash must find its way to ground over the insulated surface, has

tion to supply a substitute for these old 1 style insulators which shall be better adapted to resist the combined electrical and me chanical stresses arising under the conditions above mentioned and shall present much less serious problems in the course of manufacture;

My invention is illustrated in certain preferred forms in the accompanying drawings, wherein,

Figure l'is a side view of one of my structural insulators, Fig. 2 is a plan view of the same, Figs. 3 to T inclusiveare median sectional views of modified single members for building up this fOlIll'Of insulator, Fig. 8 is a. side view of a compound structural insulator, Fig. 9 is a horizontal section of the same on the plane ab in Fig. 8, and Fig. 10 is a sectional view of another modification.

The gist of my invention lies in the com biuation of a number of longitudinal insulating units in a framework or framed structure preferably converging toward the point of suspension of the conductorand so f arranged that the mechanical strains are created by the high tension current, but very resisted by tensional and compressive stresses only in said units. While any number of units may be used, three or four are generally sutlicient.

stood that where a bending moment exists provided withvery wide petticoats to overin any member, it is incidental to the exii gencies of practi al design, which, however,

should be such as to keep strains of that character as low as possible and much less than the tension and compression strains.

' In Figs. 1 and 2 the conductor is shown at 1, supported by a steel or iron clamp 2, suitably constructed, and placed at the point of convergence of the three straight insulating units 3. The lower extremities of these units are bolted or otherwise fastened as at ft to a suitably formed portion of the transmission line tower, shown at 5. Each 'unitcomprises an inclined central core surrounded by flanges or etticoats and pro:

Of course it will be under-.

vided at each end with a stout metal cap 6 so constructed as to facilitate securing the same to the clamp 2' or the support t as the case may be. Thesecaps are secured to the. insulating units preferably as hereinafter vided with etticoats preferably of maximum diameter near the middle of the length of each unitand diminishing in diameter toward each end. This arrangement permits the use of flanges of large diameter so placed as notto interfere with convergence of .the units and at the same time providing a certain amount of protection from rain for the smaller flanges nearer the lower ends of said units.

The insulating units" are preferably made of porcelain or glass which has been found to unite the best qualities required in insulators for high tension current which are exposed to the weather. do not limit myself to this material however- In Fig. 3 is shown a straight insulating unit- 7, made in one piece and provided with flanges of uniform diameter. The end caps 6 are cemented to the projecting ends of the i straight central core and, in order to more firmly secure these caps in place and to afford a better hold for the cement'the inner surface of each cap and the exterior surface of the insulating projection to which it is fastened are both ridged, as shown.

It. is one advantage of this invention that, inasmuch as the strains to be resisted by the insulating material are all tensional or compressive and all transverse strains are avoided, the units can be made up of sections, thus greatly facilitating the process of manufacture and insuring more uniform and reliable results.

In Fig. 4 is shown oneform of sectional insulating unit each member of which consists of-a central core 8 and one or more flanges 9, and wherein a special junction member 10 is employed comprising two opposite sleeves separated by a dividing septum into which the projecting cores of contiguous members are cemented. As shown in t-hecase of all cemented joints, I prefer to provide the opposed surfaces with ridges to give a better hold to the cement.

The use of sections having morethan one flange each is shown in Figs. 5 and 7. Figs. 5 and 6 show the use of junction members 11 wherein the dividing septumds dispensed with, and; these may or may not be provided with a petticoat or flange. In Fig. 5, the part 11 may beof metal.

Instead of junction members surrounding the projecting ends of contiguous insulating members, interior junction members 12 may be employed, and these are preferably made of steel oriron. They are shown cemented in place, but any means of securing them will be within my invention.

In Fig. 10 is shown a form of unit composed of similar sections fitting one into another.

This invention may be embodied in any combination of longitudinal insulating units arranged toresist strains by simple tension and compression, and in Figs 8 and 9 I have shown a more'complicated structure belonging to what may be termed the compound type. shown simple cylindrical insulating units,

' other forms may be employed in this connection without departing from my invention.

In the compound form shown in the draw;

ings, a number of jointed converging members unite to form a pyramidal structure, the

base of which may have three or more s1des..

From the Asquare pyramid is illustrated. base arise four lower insulating units 13,

- provided with end caps 6, as heretofore described, which caps are united by bolts 14;. or otherwise with the end caps of similar units 15 placed in the prolongation of the axes of the units 13, and converging to where they are secured to-the steel or iron clamp orv support 2. The joints betweenthe upper and lower converging units 13 and 15, being presumptively points of equal electric potential, may be braced together by. horizontal steel bars 16, as shown, and diagonal insulating units 17 are secured each to the top of one member 13 and the bottom .of the next in order.

Such a structure as that just described, or L its equivalents will resist great strains in all directions, and atthe same time will oppose From the foregoing it will be clear that the essential form of my insulating support is a. framed structure, using that term as it is commonly employed in the engineering arts to mean a structure consisting of a collection of members or elements, including members or elements joined at their extremities in groups of two or more for resolving forces acting upon the structure into components, inwhich the members or elements resisting such components are subjected substantially to longitudinal stresses only; such framed structure being preferably one in which the members which are subjected to longitudinal stresses are arranged in triangles, as, for example, in Figs. 8 and9. Here the insulating members 15 are arranged in triangles the third sides of which are formed by the metallic members 16. Likewise the. members 13 and 16 form triangles in conjunction with the members 17 and the 4 base to which the members 13'are secured.

While I have here For example, it is clear that puncturing is fatal to an insulator 1n wlnch' it occurs. In my construction, however, no puncturing and compression, having tension and compression members composed essentially of ansulatmg material, as set forth.

can occur, because the resistance to flashing 3. in insulating support for high tension discharge from the conductor to some metal part of the support is so enormously less than the resistance of the insulatin material that flashing will occur long before the potential could ever reach a voltage high; But 5 arges, (including in that term the power are which follows the first arc,

enough to puncture the insulation. flashing disc I due, say, to lightning), are not necessarily lators having wide thin petticoats, so that flashing is in general less dangerous than puncturing. In my construction, which is such that effective resistance to puncture and creeping can be obtained without excessively larg petticoats, the liability of injury by flashing is reduced to the minimum, so that in the great majority of cases where flashing occurs the insulating and supporting ca abilities of the structure will be as good a ter the flash as before. Also, the practically complete elimination of bending moments leaves only such forces as insulating material is best able to withstand, namely,'tensional and compressional forces, thus greatly reducing liability of breakage from mechanical forces originating in the conductor'by reason of weight, wind-pressure, etc.

One of the principal advantages which follow from the use of this improvement is, that one is able to dispense with any metallic core extending into the insulator. These cores have been resorted to in the past in order to resist transverse strains, andit has been found that their presence, owing to electrical conditions not fully explained, greatly increases the tendency to flashing around the insulator through the air from the conductor to the ground. By resolving all the strains set up by the conductor into substantially pure tension or compression in the insulating units, I am able to dispense with these metallic cores and so greatly lessen this tendency to flashing.

-My invention is capable of embodiment in many forms without departing from the spirit of my invention, and I do not limit myself to the details herein shown and described.

\VhatI claim is I 1. An insulating support for high tension conductors, comprising a framed structure, for resolving mechanical forces originating in the conductor into components, having structural members essentially of insulating material for resistings'uch components, as set forth.

An insulating support for high tension conductors, comprising a framed structure, for resolving mechanical forces ori 'nating in the conductor into components 0 tension at its ends, as set forth.

conductors, con'iprismg a framed structure, for resolvingmechanical forces originating in the conductor into components, having insaluting members convergent toward the conductor for resisting such components, as sc-tforth. v s

4. An insulating support for high tension conductors, comprising a framed structure,

5 for res ..-lving mecl'ianic'al forces originating fatal thou h usually so in the case of msuin the conductor into components, having component-resistant members each consisting of an elongated body of insulating material provided with metal connecting caps 5. An insulating support for high tension conductors, comprising a framed structure, for resolving mechanical forces originating in the conductor into components, having members, for resisting such components, each composed of a number of complete insulating units joined together in a straight line, as set forth.

6. An insulating support for high tension conductors, comprising a framework having insulating structural members arranged in triangles, as set forth.

7. An insulating support for high tension conductors comprising a pyramidal framework having insulating structural members arranged in triangles, as set forth.

8. An insulating support for high tension conductors comprising a framed structure having insulating structural members, and metallic members extending between equipotential points of the framework, as set forth. v

9. An insulating support for high tension conductors, comprising a pyramidal framework having insulating structural members arranged in triangles, and metallic members extending between equi-potential points of the framework, as set forth.

.10. An insulating support for high tension conductors, comprising a plurality of insulating structural members converging in pyramidal form toward the conductor, and metallic cross members extending between points of equal potential in the framework,

as set forth.

l1. Aninsulating support for high tension conductors, comprising a plurality of insulating members converging toward a common apex, metallic members extending between the upper ends of the said converg- ;i ng members, forming a framework of trun- 12. An insulating sun'port for a high tension conductor comprising a framework composed of braced converging members each or" which consists of insulating-units 5 having metzil caps, said units being united by joining their contiguous metal caps, substantially as described. I

13. in an insulating support for high tension conductors, an insulating unit composed of sections of insulating material and insulating junction pieces fitting over and cemented to adjoining ends of said sections, each junction piece comprising a transverse septum separating the sections, substantially 5 as described.

1%. An insulating support for high ten- I craves sion conductors, comprising a plurality of elongated members of insulating material joined together at their extremities into a framed structure, as set forth.

15. An insulating support for high tension conductors, comprising a. plurality of elongated members of insulating material joined together at their extremities into :1 framed-structure, and a device for carrying a conductor mounted at the juncture of three or moreof said members, as sei: forth.

' uALPn n. Mnnsnon. Witnesses Earner; Roemsou, HARRY iJ. S. GEORGE. 

